74 II. DIGESTION AND ABSORPTION OF FATS 



bile. 429 Lithocholic acid has been shown to be 3-hydroxycholanic acid in 

 which the hydroxy on C 3 has assumed the trans position. 430 This trans 

 position of the hydroxyl in lithocholic acid is thus similar to that found for 

 the corresponding group in cholic, desoxycholic, and chenodesoxycholic 

 acids. 



Hyodesoxycholic acid (Gr. vs swine) was originally discovered in hog 

 bile, as early as 1847, by Gundelach and Strecker. 431 More recently its 

 presence in bile from this animal has been reaffirmed. 414 ' 415 It has been 

 found to be present in two isomeric forms, described as the a- and /3-acids. 

 Trickey 415 has reported that 40% of the bile acids in hog bile consist of 

 hyodesoxycholic acid. 



a-Lagodesoxycholic acid, which was discovered by Kishi 432 in rabbit bile, 

 was considered by this investigator to be a C n epimer of desoxycholic acid. 

 It is now believed to have a different configuration, since the authentic 

 12-epidesoxycholic acid obtained from 3-hydroxy-12-ketocholanic acid 

 differs in melting point from the natural a-lagodesoxycholic acid. 433 



Haslewood and Wootton 434 ' 435 reported that the bile of three species of 

 Boidae, namely the Boa constrictor occidentalis (Western boa), Python 

 molurus (Indian "tiger" python), and Python sebae (African python), 409 

 contains a hitherto unknown bile acid, which is called pythocholic acid 

 and which has an empirical formula of C24H40O5. This was shown to be 

 readily converted into pythocholic lactone, C04H38O4, by the loss of one mole- 

 cule of water. In earlier communications, 434 these compounds were re- 

 ferred to as "pythonic acid" and "pythonic lactone." In the case of the 

 African python (Python sebae), pythocholic acid, conjugated with taurine, 

 formed the main constituent of the bile salts. Kuroda and Arata, 425 also, 

 isolated pythocholic lactone from the bile of the reticulated python (Python 

 reticulatus) . Haslewood 436 has confirmed the presence of this lactone in the 

 reticulated python, as well as in an additional species of Boidae, namely the 

 anaconda or aquatic boa (Eunectes murinus). 



Pythocholic acid was shown to make up 50 to 70% of the total bile acids 

 in seven species of Boidae. iS5 The acid has three potential hydroxyl 

 groups, i.e., 3, 12, and 16 or 15. 435,436 The configuration of the hydroxyls 



429 H. Sobotka and E. Bloch, Ann. Rev. Biochem., 12, 45-80 (1943). 



430 L. Ruzicka and M. W. Goldberg, Helv. Chim. Acta, 18, 668-675 (1935). 



431 C. Gundelach and A. Strecker, Ann., 62, 205-232 (1847); A. Strecker and C. 

 Gundelach, Ann. chim. phys., [8], 22, 38-59 (1848). 



432 S. Kishi, Z. physiol, Chem., 238, 210-220 (1936). 



433 B. Koechlin and T. Reichstein, Helv. Chim. Acta, 25, 918-935 (1942). 



434 G. A. D. Haslewood and V. M. Wootton, Biochem. ./., 46, x (1950). 



436 G. A. D. Haslewood and V. M. Wootton, Biochem. J., 49, 67-71 (1951). 

 436 G. A. D. Haslewood, Biochem. J., 49, 718-720 (1951 ). 



